Last summer we had the pleasure of visiting the home of Mr. Wesley Ellis to document (3D scanning, photography, and metadata) his collection of Caddo ceramics. We still have some work ahead of us as we delve into the specific context of each vessel, and consider how the results of the morphometrics study might best augment a more traditional analysis. We are currently reaching out to our colleagues to explore how these data might best be couched within current theoretical dialogues.
Using the method discussed in our last post (see that here), we imported these data to Morphologika 2.5 for a generalized Procrustes analysis (GPA) and principal components analysis (PCA).
The Procrustes coordinates were then exported to R, where we conducted a hierarchical cluster analysis (Complete Linkage/Euclidian Distance), which grouped those vessels that are most similar in shape. In addition to the metric data, a wide range of qualitative data (temper, firing, paste, etc.) were added to the dataset prior to the Morphologika import, and have accompanied the metric data into R, where they will be used to better illustrate qualitative attributes in the various quantitative plots.
We are in the process of collecting these same data from the remainder of our 3D models, and will soon have them reformatted and aggregated for a much larger synthetic analysis that will include ceramic vessels from the Washington Square Mound and Vanderpool sites, as well as the McSpadden, Middlebrook, Ellis, and Turner Collections.
This synthesis will serve as the foundation for a more in-depth study of Caddo vessel morphology, adding to dialogues of ceramic technological organization, and augmenting current theoretical avenues/lines of inquiry aimed at highlighting how ceramic vessel design (and use?) may have evolved within the southwestern Caddo region.
The principal benefit of this systematic approach to the classification of ceramic vessel morphology is that those hypotheses we put forth can be affirmed or refuted with the addition of new data (in this case, 3D scans populated with landmark/semi-landmark data). As an ancillary benefit, the 3D models of Caddo ceramic vessels from private, as well as public, collections will soon be available for download in our new digital repository (although you can currently explore/manipulate a selection of our scans here). Our plans are to put the resulting comparative collection of 3D models, photographs and metadata to good use as we continue to explore the variation in Caddo ceramic vessels, while keeping an ever-watchful eye out for shifting elements of vessel shape that might signal a transition from one vessel shape to another through time.